JP2021504170A - Coated polishing disc and its manufacturing method and usage method - Google Patents

Abstract

The coated polishing disc includes a disc backing having an outer circumference. The polishing layer is placed on top of the disc backing. The polishing layer comprises a triangular polishing strip secured to the main surface of the disc backing by at least one binder material. Triangular abrasive strips are located at least 70 percent of the regularly spaced locations along an arithmetic spiral pattern that extends outward toward the outer circumference. Each of the triangular polished plates has its own top and bottom surfaces connected to each other and separated by three side walls. Each side wall of at least 90 percent of each of the triangular polished plaques faces the disc backing and is located close to the disc backing, longitudinally within 10 degrees tangential to the arithmetic spiral pattern. It is aligned. Also disclosed are methods of manufacturing and using coated polished discs.

Description

The present disclosure relates, in a broad sense, to coated abrasive discs, their manufacturing methods and their use.

Coated polishing discs made from triangular polishing strips are useful for polishing, finishing or grinding a wide variety of materials and surfaces in the manufacture of commodities. In particular, high pressure off-hand grinding of carbon steel by off-hand polishing using a handheld right angle grinding machine is an important application for coated polishing discs. In view of the above, there continues to be a need to improve the cost, performance and / or life of coated polished discs.

A coated polished article having a rotatably aligned triangular polishing strip is disclosed in US Pat. No. 9,776,302 (Keipert). The coated polished article has a plurality of triangular polished strips having individual surface features. The plurality of triangular polishing plates are attached to the flexible backing by a make coat containing a resinous adhesive that forms a polishing layer. The surface feature has a defined Z-axis rotation arrangement direction, which occurs more frequently in the polishing layer than would be caused by the random Z-axis rotation arrangement direction of the surface feature. ..

In one aspect, the present disclosure
Disc backing with outer circumference and
A polishing layer placed on top of the disc backing, comprising a triangular polishing plate that is secured to the main surface of the disc backing by at least one binder material, with the triangular polishing plate extending outward toward the outer circumference. With a polishing layer, which is located at least 70 percent of the regularly spaced locations along the arithmetic spiral pattern,
Each of the triangular polished plates has its own top and bottom surfaces connected to each other and separated by three side walls.
Each side wall of at least 90 percent of each of the triangular-polished plaques faces the disc backing and is located close to the disc backing, longitudinally within 10 degrees tangential to the arithmetic spiral pattern. Provided is a coated polishing disc to be aligned.

Advantageously, the coated polishing discs according to the present disclosure are useful for high pressure off-hand polishing of carbon steel, and they exhibit superior performance as compared to similar conventional discs.

Thus, in a second aspect, the present disclosure provides a method of polishing a workpiece, the method of frictionally contacting a portion of the polishing layer of a coated polishing disc according to the present disclosure with the workpiece and polishing the workpiece. This includes moving at least one of the workpiece and the coated abrasive disc with respect to the other.

In a third aspect, the present disclosure provides a method of making a coated abrasive disc, the method of which is:
Placing the curable make-up layer precursor on the main surface of the disc backing,
Adhesion of the triangular-polished plates into the curable make-up layer precursor, where the triangular-polished plates are regularly spaced along an arithmetically spiral pattern that extends outward toward the outer circumference. Located at least 70 percent,
The triangular polishing plate comprises a triangular polishing plate, and each of the triangular polishing plates has a top surface and a bottom surface, which are connected to each other and separated by three side walls.
Each side wall of at least 90 percent of each of the triangular polished plates is placed in close proximity to the disc backing and aligned longitudinally within 10 degrees tangential to the arithmetic spiral pattern. , Gluing and
To provide a make-up layer by at least partially curing the curable make-up layer precursor.
Placing the curable size layer precursor on the make-up layer and the triangular polishing plate,
Curable Size Layer The precursor is at least partially cured to provide a size layer.

As used herein,
The term "mild steel" means a carbon-based steel alloy containing less than about 0.25 weight percent carbon.
The term "off-hand polishing" means polishing where the operator manually urges the disc / wheel against the workpiece and vice versa.
The term "proximity" means very close or adjacent (eg, in contact with or embedded in the binder layer).
The term "helix" means a plane spiral. In some preferred embodiments, the spiral may be an arithmetic spiral, also known as the "Archimedean spiral". Arithmetic spirals have the property that any light beam from the origin intersects the continuous rotation of the helix at a point with a certain separation distance.

The term "workpiece" means something that has been polished.

As used herein, the term "triangular abrasive plate" refers to at least a portion of abrasive particles having a predetermined shape that are replicated from the mold cavity used to form the shaped precursor abrasive particles. It means ceramic abrasive particles having. Except for the case of polishing debris (eg, as described in US Patent Application Publication No. 2009/0169816 (A1) (Erickson et al.)), Triangular polishing plates are generally used to form triangular polishing plates. It will have a predetermined geometry that substantially duplicates the mold cavity used. As used herein, triangular polishing strips exclude randomly sized abrasive particles obtained by mechanical crushing operations.

As used herein, the "Z-axis rotational arrangement direction" is the longitudinal dimension of the side wall of the triangular polished disc that faces the disc backing most around the Z axis perpendicular to the main surface of the disc backing. It means the angular rotation of.

The features and advantages of the present disclosure will be further understood by considering the detailed description and the appended claims.

It is a schematic top view of the exemplary coated polishing disc 100. It is an enlarged view of the area 1A of FIG. It is an enlarged view of the region 1B of FIG. 1A. It is the schematic sectional drawing of the coating polishing disk 100 taken along the line 1C-1C of FIG. 1B. It is a schematic top view of the exemplary triangular polishing small plate 130a. It is the schematic perspective view of the exemplary triangular polishing small plate 130a. It is a schematic top view of the exemplary triangular polishing small plate 330b. It is a schematic side view of the exemplary triangular polishing small plate 330b. It is a schematic top view of the production tool 400 useful for manufacturing a coated polishing disk 100. It is an enlarged view of the area 4A of FIG. It is an enlarged view of the area 4B of FIG. 4A. FIG. 6 is an enlarged schematic cross-sectional view of the production tool 400 taken along line 4C-4C of FIG. 4B, showing the cavity 420. FIG. 6 is an enlarged schematic cross-sectional view of the production tool 400 taken along line 4D-4D of FIG. 4B, showing the cavity 420.

Repeated use of reference characters herein and in the drawings is intended to represent the same or similar features or elements of the present disclosure. Those skilled in the art can devise many other modifications and embodiments, and it should be understood that they fall within the scope and intent of the principles of the present disclosure. The figure may not be drawn to scale.

FIG. 1 shows an exemplary coated polishing disc 100 according to the present disclosure, in which the triangular polishing plate 130 is fixed in an accurate position to the disc backing 110 in the Z-axis direction.

Here, reference is made to FIGS. 1 and 1A to 1C in which the polishing layer 120 is arranged on the main surface 115 of the disc backing 110. The polishing layer 120 comprises a triangular polishing plate 130 secured to the main surface 115 of the disc backing 110 by at least one binder material (shown as make-up layer 132 and size layer 134). The optional super size layer 156 is placed on top of the size layer 134. The triangular polishing strips 130 are arranged at regularly spaced locations 138 along an arithmetic spiral pattern 140 extending outward toward the outer circumference 142. At least 90 percent of each side wall of each of the triangular polished strips 130 facing the disc backing and placed in close proximity to the disc backing is tangential to the arithmetic helix pattern 140 at the corresponding location 138. It is vertically aligned within 10 degrees from. In this regard, collinear and parallel configurations should be considered aligned at zero degrees with respect to the tangent.

The disc backing can include, for example, any known coating polishing backing. In some embodiments, the disc backing comprises a continuous, uninterrupted disc, while in other embodiments, the disc backing can have a central arbor hole for mounting. Similarly, the disc backing may be flat or may have a pressed central hub, eg, a depressed central disc of Type 27. The disc backing may be rigid, semi-rigid, or flexible. In some embodiments, the backing has a mechanical fastener, or an adhesive fastener that is firmly attached to the main surface opposite the polishing layer. Suitable materials for substrates include polymerized films, metal foils, woven fabrics, knitted fabrics, paper, vulcanized fibers, non-woven fabrics, foams, screens, laminates, combinations thereof, and treated versions thereof. .. Vulcanized fiber backing is usually preferred for off-hand grinding applications where rigidity and cost are a concern. In applications where the backing rigidity is desired, flexible backing can also be used by attaching to a rigid backup pad attached to the grinding tool.

The disc backing is generally circular, preferably rotationally symmetric around its center. The disc backing preferably has a circular perimeter, but may have additional features along the perimeter, for example in the case of a scalloped perimeter.

The polishing layer can include a single binder layer with abrasive particles retained therein, and more typically can have a multi-layer structure with a make-up layer and a size layer. The coated polishing disc according to the present disclosure can include an additional layer such as an optional super-sized layer superimposed on the polishing layer, or can optionally include a backing antistatic treatment layer. .. Suitable exemplary binders can be prepared from thermosetting resins, radiation curable resins and combinations thereof.

The make layer can be formed by coating the main surface of the backing with a curable make layer precursor. The make layer precursor is, for example, an adhesive, a phenol resin, an aminoplast resin, a urea-formaldehyde resin, a melamine-formaldehyde resin, a urethane resin, a free group polymerizable polyfunctional (meth) acrylate (for example, pendant α, β-unsaturated). It can contain groups, acrylated urethanes, acrylated epoxies, aminoplast resins with acrylated isocyanurates), epoxy resins (including bis-maleimide and fluorene modified epoxy resins), isocyanurate resins and mixtures thereof. Of these, phenolic resins are preferred, especially when used in combination with vulcanized fiber backing.

Phenol resins are generally formed by condensation of phenol and formaldehyde and are usually classified as resole resins or novolac phenol resins. Novolac phenol resin is acid catalyzed and has a molar ratio of formaldehyde to phenol less than 1: 1. The resol-phenol resin can be catalyzed by an alkaline catalyst and has a formaldehyde to phenol molar ratio of 1 or greater, typically 1.0 to 3.0, providing a pendant methylol group. To do. Suitable alkaline catalysts for catalyzing the reaction between the aldehyde and the phenolic component of the resol-phenolic resin include sodium hydroxide, barium hydroxide, potassium hydroxide, calcium hydroxide, organic amines and sodium carbonate. All of these are as a solution of the catalyst dissolved in water.

The resole-phenolic resin is typically coated as a solution with water and / or an organic solvent (eg, alcohol). Typically, the solution comprises from about 70 weight percent to about 85 weight percent solid, but other concentrations may be used. If the solid content is very low, more energy is needed to remove the water and / or solvent. If the solid content is extremely high, the resulting phenolic resin will become too viscous, typically leading to processing problems.

Phenol forms are well known and are readily available from commercial sources. Examples of commercially available resole-phenol resins useful in the practice of the present disclosure are resole-phenol resins sold by Durez Corporation under the trade names VARCUM (eg 29217, 29306, 29318, 29338, 29353). , Under the trade name AEROFENE (eg, AEROFENE 295), Ashland Chemical Co., Ltd., located in Bartow, Florida. Resol phenol resin sold by PHENOLITE (eg, PHENOLITE TD-2207), Gangnam Chemical Company Ltd., located in Seoul, South Korea. Examples include resole-phenolic resins sold by.

Make layer precursors are added by any known coating method for adding make layers to backing, such as roll coatings, extruded die coatings, curtain coatings, knife coatings, gravure coatings and spray coatings. be able to.

The weight of the make-up layer utilized may depend, for example, on the intended use, the type of abrasive particles, and the nature of the coated abrasive disc being prepared, but is typically 1, 2, 5, 10, or 15. It ranges from grams / square meter (gsm) to 20, 25, 100, 200, 300, 400 and even 600 gsm. The make-up layer is any known for adding a make-up layer (eg make-up coat) to the backing, including, for example, roll coatings, extruded die coatings, curtain coatings, knife coatings, gravure coatings and spray coatings. It can be added depending on the coating method used.

When the make-up layer precursor is coated on the backing, a triangular-polished plate is added to and embedded in the make-up layer precursor. Triangular polishing strips are nominally added onto the make-up layer precursor according to a predetermined pattern and Z-axis rotational arrangement direction.

Triangular polishing strips are arranged at regular intervals (ie, separated at regular intervals) along an arithmetic spiral pattern that extends outward toward the outer circumference. At least 70 percent (eg, at least 80 percent, or at least 90 percent, and even at least 95 percent) of location 138 is laid out with one of the triangular polishing plates. The arithmetic spiral pattern can cover part of the main surface of the disc backing or the entire backing.

Next, referring to FIGS. 2A and 2B, each of the triangular abrasive plates 130 has a top surface and a bottom surface (162, 164) connected to each other and separated by three side walls 166a, 166b, 166c. Have.

One side wall 166a of at least 90 percent (eg, at least 95 percent, at least 99 percent, and even 100 percent) of the triangular polished plaque 130 is located facing the disc backing 110 (preferably in close proximity to the disc backing). (See Figure 1C). Further, the individual side walls 166 facing the disc backing 110 are within 10 degrees (preferably within 5 degrees) tangent to the arithmetic helix pattern at each location 138 where the individual side walls 166 are located. , More preferably within 2 degrees) has a horizontal Z-axis 141 rotation arrangement direction θ.

3A and 3B show another embodiment of the useful triangular abrasive plate 330, which are connected to each other and separated by three inclined side walls (336), respectively. It has a top surface and a bottom surface (332, 334).

In this regard, the horizontal Z-axis rotation direction is 10 from the tangent at the point on the spiral pattern if its Z-axis projection onto the arithmetic spiral pattern 140 (which is flat) intersects the tangent at an angle of 10 degrees or less. It is considered to be within degrees. Collinear and parallel configurations are considered to intersect tangents at an angle of zero.

In some preferred embodiments, the spacing between each point on the arithmetic helix pattern is 1-3 times the average length of the side wall of the triangular-polished plate facing the fiber disc backing, more preferably. Is 1.2 to 2 times, more preferably 1.2 to 1.7 times, but other intervals can also be used.

It is permissible that some of the regularly spaced locations along the arithmetic spiral may not have the triangular-polished plaques located at that location. In a preferred embodiment, at least 70 percent (preferably at least 80 percent, more preferably at least 90 percent, more preferably at least) of regularly spaced contact points adjacent to the area occupied by the triangular abrasive strips. At 95%), triangular polished strips are placed.

In some embodiments, the triangular-polished plate is shaped as a thin triangular prism, while in other embodiments, the triangular-polished plate is as a truncated triangular pyramid (preferably having a taper angle of about 8 degrees). It is shaped. Triangular polished plates can have different side lengths, but are preferably equilateral on their maximum plane.

The triangular polishing strip has sufficient hardness to function as polishing particles in the polishing process. The triangular polished plate preferably has a Mohs hardness of at least 4, at least 5, at least 6, at least 7, and even at least 8. They preferably contain alpha alumina.

The crushed or non-abrasive particles are substantially the largest of the nominally defined grade particles that can be retained in the abrasive layer between the abrasive elements and / or between the abrasive plates, preferably in a closed coat (ie, in the abrasive layer). It may be contained in an amount sufficient to form a possible number).

Examples of suitable abrasive particles are molten aluminum oxide, heat treated aluminum oxide, white molten aluminum oxide, trade name 3M CERAMIC ABRASIVE GRAIN, St. Minnesota. Ceramic aluminum oxide materials such as ceramic aluminum oxide materials commercially available from Paul's 3M Company, brown aluminum oxide, blue aluminum oxide, silicon carbide (including green silicon carbide), titanium diboride, carbonized Boron, Tungsten Carbide, Garnet, Titanium Carbide, Diamond, Cubic Borone Nitride, Garnet, Fused Alumina Zirconia, Iron Oxide, Chromia, Zirconia, Titania, Tin Oxide, Quartz, Changstone, Pine Stone, Kongo Sand, Sol-Gel Induced Polish Examples include particles and combinations thereof. Of these, molded sol-gel-derived alpha-alumina triangular polished strips are preferred in many embodiments. Abrasives that cannot be treated by the sol-gel pathway can be molded using a temporary or permanent binder, which forms shaped precursor particles and then is sintered. Thus, for example, the triangular abrasive strips described in US Patent Application Publication No. 2016/0068729 (A1) (Erickson et al.) Are formed.

Examples of sol-gel-induced abrasive particles and methods for preparing them are U.S. Pat. Nos. 4,314,827 (Leetheiser et al.), 4,623,364 (Cottringer et al.), 4,744. , 802 (Schwabel), 4,770,671 (Monroe et al.) And 4,881,951 (Monroe et al.). Further, the polishing particles may include, for example, polishing agglomerates such as the polishing agglomerates described in US Pat. No. 4,652,275 (Bloecher et al.) Or No. 4,799,939 (Bloecher et al.). Is also planned. In some embodiments, the triangular abrasive plate is a coupling agent (eg, an organosilane coupling agent) or the like to enhance the adhesion of the abrasive particles to the binder (eg, make-up layer and / or size layer). The surface can be treated with the physical treatment of (for example, iron oxide or titanium oxide). The abrasive particles can be treated prior to binding them to the corresponding binder precursor, or the abrasive particles can be surface treated in situ by including a coupling agent in the binder.

The triangular polishing strip preferably contains ceramic polishing particles such as sol-gel-derived polycrystalline alpha-alumina particles. Triangular polished small plates composed of alpha alumina, magnesium alumina spinel and rare earth hexagonal aluminate crystals are described, for example, in US Pat. No. 5,213,591 (Celikkaya et al.) And US Patent Application Publication No. 2009 / It can be prepared using sol-gel precursor alpha-alumina particles by the methods described in 0165394 (A1) (Culler et al.) And 2009/0169816 (A1) (Erickson et al.).

Alpha-alumina-based triangular polished strips can be manufactured according to the well-known multi-step process. Briefly, the method comprises the steps of producing either seeded or non-seeded sol-gel alpha-alumina precursor dispersion that can be converted to alpha-alumina and the desired external shape. A step of filling one or more mold cavities with a triangular polishing platen with sol-gel, a step of drying the sol-gel to form a precursor triangular polishing plateau, and a mold cavity of the precursor triangular polishing plateau. Steps to remove from, and steps to calcinate the precursor triangle-polished plaque to form a calcinated precursor triangle-polished plaque, and then to calcinate the calcinated precursor triangle-polished plaque. Including the step of forming a triangular polishing plate. The process will be described in more detail below.

Further details regarding the method for producing sol-gel-induced abrasive particles are described, for example, in US Pat. Nos. 4,314,827 (Leitheaser), 5,152,917 (Pieper et al.), 5,435,816. (Spurgeon et al.), No. 5,672,097 (Hoopman et al.), No. 5,946,991 (Hoopman et al.), No. 5,975,987 (Hoopman et al.), And No. 6,129. , 540 (Hoopman et al.), And US Patent Application No. 2009/0165394 (A1) (Culler et al.).

The triangular polishing plate can include a single type of triangular polishing plate or a blend of two or more sizes and / or compositions of the triangular polishing plate. In some preferred embodiments, the triangular-polished plate is essentially a molding tool or means of production in which the individual triangular-polished plates are dried prior to the optional baking and sintering. It will have a shape that is the shape of the hollow portion.

The triangular-polished flakes used in the present disclosure are typically tools cut using precision machining that provide higher feature demarcation than other manufacturing alternatives, such as punching or punching. Manufactured using a mold). Typically, the cavity on the tool surface has a matching flat surface along the sharp edges, forming the sides and apex of the truncated pyramid. The resulting triangular-polished plate has a nominal average shape, which corresponds to the shape of the cavity on the tool surface (eg, truncated pyramid), but changes from the nominal average shape (eg, random changes). ) May occur during production, and triangular-polished plates exhibiting such changes are included within the definition of triangular-polished plates used herein.

In some embodiments, the base and top of the triangular-polished plate are substantially parallel, resulting in a prismatic or truncated pyramidal shape, but this is not a requirement. In some embodiments, the sides of the truncated triangular prism have equal dimensions and form a dihedral angle of approximately 82 degrees with the base. However, it will be recognized that other dihedral angles (including 90 degrees) can be used as well. For example, the dihedral angle between each of the base and the sides may independently range from 45 to 90 degrees, typically 70 to 90 degrees, and more typically 75 to 85 degrees.

As used herein in reference to a triangular-polished plate, the term "length" means the maximum dimension of a triangular-polished plate. "Width" means the maximum dimension of a triangular polished plate that is perpendicular to its length. The term "thickness" or "height" means the dimensions of a triangular-polished plate that is perpendicular to length and width.

Examples of sol-gel-induced triangular alpha-alumina (ie ceramic) abrasive particles are US Pat. Nos. 5,201,916 (Berg), 5,366,523 (Lowenhorst (Re 35,570)), and It can be found in No. 5,984,988 (Berg). Details regarding such abrasive particles and methods for preparing them are described, for example, in US Pat. Nos. 8,142,531 (Adefris et al.), 8,142,891 (Culler et al.) And 8,142. , 532 (Erickson et al.), And US Patent Application Publication Nos. 2012/0227333 (Adefris et al.), 2013/0040537 (Schwabel et al.) And 2013/0125477 (Adefris).

Triangular polished plates are typically selected to have lengths in the range of 1 micron to 15000 microns, more typically 10 microns to about 10000 microns, and even more typically 150 to 2600 microns. However, other lengths can be used as well.

Triangular polished strips are typically selected to have a width in the range of 0.1 micron to 3500 microns, more typically 100 to 3000 microns, and more typically 100 to 2600 microns. However, other lengths can be used as well.

Triangular ground plates are typically selected to have a thickness in the range of 0.1 micron to 1600 microns, more typically 1 micron to 1200 microns, but using other thicknesses. May be good.

In some embodiments, the triangular-polished plate can have an aspect ratio (length vs. thickness) of at least 2, 3, 4, 5, 6 or higher.

The surface coating on the triangular polishing disc can be used to improve the adhesion between the triangular polishing plate and the binder in the coated polishing disc, or to promote electrostatic deposition of the triangular polishing plate. it can. In one embodiment, the surface coating described in US Pat. No. 5,352,254 (Celikkaya) is used in an amount of surface coating of 0.1 to 2 percent based on the weight of the triangular polished plate. Can be done. Such surface coatings are described in US Pat. Nos. 5,213,591 (Celikkaya et al.), 5,011,508 (Wald et al.), 1,910,444 (Nicholson), No. 3, 041,156 (Rouse et al.), 5,09,675 (Kunz et al.), 5,085,671 (Martin et al.), 4,997,461 (Markoff-Matheny et al.) And It is described in the same No. 5,042,991 (Kunz et al.). In addition, the surface coating can prevent capping of the triangular polished strips. Capping is a term that describes the phenomenon in which metal particles from a workpiece being polished become welded to the top of a triangular abrasive plate. Surface coatings that perform the above functions are known to those skilled in the art.

Abrasive particles can be independently sized according to the specified nominal grades recognized in the polishing industry. Examples of grading standards recognized in the polishing industry include ANSI (American National Standards Institute, American National Standards Institute), FEPA (Federation of European Products of Abrasives, European Federation of Abrasive Producers, Japanese Industrial Standards Institute) and JIS (American National Standards Institute) and JIS (American National Standards Institute). Those promulgated by the Japanese Industrial Standards) can be mentioned. ANSI grade designations (ie defined nominal grades) include, for example, ANSI4, ANSI6, ANSI8, ANSI16, ANSI24, ANSI36, ANSI46, ANSI54, ANSI60, ANSI70, ANSI80, ANSI90, ANSI100, ANSI120, ANSI150, ANSI180, ANSI220, ANSI240, ANSI280. , ANSI320, ANSI360, ANSI400 and ANSI600. FEPA grade designations include F4, F5, F6, F7, F8, F10, F12, F14, F16, F16, F20, F22, F24, F30, F36, F40, F46, F54, F60, F70, F80, F90, Examples thereof include F100, F120, F150, F180, F220, F230, F240, F280, F320, F360, F400, F500, F600, F800, F1000, F1200, F1500 and F2000. As JIS grade designation, JIS8, JIS12, JIS16, JIS24, JIS36, JIS46, JIS54, JIS60, JIS80, JIS100, JIS150, JIS180, JIS220, JIS240, JIS280, JIS320, JIS360, JIS400, JIS600, JIS800, JIS1000, JIS1 Examples thereof include JIS2500, JIS4000, JIS6000, JIS8000 and JIS10000. According to one embodiment of the present disclosure, the average diameter of the abrasive particles may be in the range of 260 to 1400 microns according to FEPA grades F60 to F24.

Alternatively, U.S.A., which complies with ASTM E-11 "Standard Specialization for Wire Cross and Specifications for Testing Purposes". S. A. Abrasive particles can be rated to a nominally reviewed grade using the Standard Test Sieves. ASTM E-11 defines the requirements for the design and construction of test sieves using a woven wire mesh medium mounted in a frame to classify materials according to a specified particle size. A typical designation can be expressed as -18 + 20, which means that the abrasive particles pass a test sieve that meets the ASTM E-11 specifications for sieve # 18 and the ASTM E-11 specifications for sieve # 20. Means that it is held on a test sieve that meets the requirements. In one embodiment, the abrasive particles have a particle size such that most of the particles pass through an 18 mesh test sieve and can be retained on a 20, 25, 30, 35, 40, 45 or 50 mesh test sieve. doing. In various embodiments, the abrasive particles are -18 + 20, -20 / + 25, -25 + 30, -30 + 35, -35 + 40, 5-40 + 45, -45 + 50, -50 + 60, -60 + 70, -70 / + 80, -80 + 100, -100 + 120. , -120 + 140, -140 + 170, -170 + 200, -200 + 230, -230 + 270, -270 + 325, -325 + 400, -400 + 450, -450 + 500 or -500 + 635 can have a nominally examined grade. Alternatively, a custom mesh size such as -90 + 100 can be used.

Arithmetic spiral patterns are characterized by their pitch (ie, regular separation between the lines of the spiral pattern) as they move radially outward from the actual or theoretical center of the spiral pattern. be able to. In some preferred embodiments, the arithmetic helix pattern pitch is 1.2 to 3 times, more preferably 1.2 to 2.5 times, even more preferably 1.2 times the thickness of the triangular polished plate. ~ Double, but this is not a requirement. Similarly, in some preferred embodiments, the regularly spaced intervals are 1-3 times, more preferably 1.2 to 2 times, even more preferably 1. It is 2 to 1.5 times, but this is not a requirement.

The coated polishing disc according to the present disclosure can be manufactured by a method in which a triangular polishing plate is accurately placed and the placement direction is determined. The method usually involves filling the cavities in the means with one or more triangular polishing plates (typically one or two), respectively, and making the filled production tools and triangular polishing plates. Includes a step of aligning the make-up layer precursor coating backing for transfer to the layer precursor, a step of transferring the abrasive particles from the cavity onto the make-up layer precursor coating backing, and a step of removing the means from the aligned position. .. The make-up layer precursor is then at least partially cured (typically to the extent that the triangular-polished sheet metal is firmly adhered to the backing), and then the size layer precursor is the make-up layer precursor and It is added on top of the abrasive particles and at least partially cured, thereby providing a coated abrasive disc. The process, which may be batch or continuous, can be practiced by hand or automated using, for example, a robotic device. It is not necessary to perform all the steps, or they need to be performed sequentially, but these steps can be performed in the order listed, or additional steps can be performed between them. You may.

Triangular abrasive plates are initially placed in a properly shaped cavity in the distribution surface of the means of production arranged to have a complementary arithmetic helix pattern in the desired rotational placement direction (eg, for example. It can be placed in the Z-axis rotation arrangement direction).

An exemplary production tool 400 for manufacturing the coated polishing disc 100 formed by casting the thermoplastic sheet 415, shown in FIGS. 1 and 1A to 1C, is shown in FIGS. 4 and 4A to 4D. It is shown in. Next, referring to FIGS. 4 and 4A-4D, the means of production tool 400 is a distribution surface 410 with an arithmetic spiral pattern 430 of a cavity 420 sized and shaped to receive a triangular abrasive plate. have. The cavities 420 are aligned in a Z-axis rotation, so that when the triangular-polished plates are filled, they are subsequently transferred as they are transferred, and they are the desired corresponding arithmetic in the resulting coated abrasive disc. It forms a spiral pattern and a Z-axis rotation arrangement direction.

When almost or all cavities are filled with the desired number of triangular-polished plates, the distribution surface is brought close to or in contact with the make-up layer precursor layer on the disc backing, thereby making it nominally horizontal. While maintaining the orientation, the triangular abrasive strips are transferred from the means of production by adhering (eg, embedding and / or contacting) to the make-up layer precursor. Of course, some unintended loss in the placement direction can occur, but in general, the loss in the placement direction should be manageable within a tolerance of ± 10 degrees or less.

In some embodiments, the depth of the cavity in the means of production is selected so that the triangular abrasive platelets fit perfectly into the cavity. In some preferred embodiments, the triangular-polished plaque extends slightly beyond the opening of the cavity. According to this method, they can be transferred to the make-up layer precursor by direct contact, and the chances of the resin being transferred to the production tool are reduced. In some preferred embodiments, when the triangular polishing plate is completely inserted into the cavity, the center of mass of the individual triangular polishing plate is present within each cavity of the means of production tool. If the depth of the cavity becomes too shallow, the center of mass of the triangular polishing plate is located outside the cavity, the triangular polishing plate is not easily held in the cavity, and when the means of production is used in the equipment, Triangular polishing plaques can jump off.

It is preferable that an excess of triangular polishing plates is added to the distribution surface of the production tool so that more triangular polishing plates are provided to fill the cavities in the production tool. Excessive triangular polishing plates, which means that the number of triangular polishing plates present per unit length of the means of production is greater than the number of cavities present, causes the triangular polishing plates to accumulate on the distribution surface. And, as they move around by either gravity or other mechanically applied force, thereby moving in parallel into the cavity, most of the cavity in the means of production is finally filled with triangular-polished plates. Promote assurance that it will be done. Bearing areas and spacing of abrasive particles are often designed for a particular grinding application in the means of production, so it is usually desirable not to have excessive variability in the number of unfilled cavities.

Most of the cavities in the distribution surface are preferably filled with triangular-polished slabs arranged in the individual cavities so that the cavities and the sides of the slabs are at least approximately parallel. This can be achieved by shaping cavities that are slightly larger than the triangular ground plate (or more). To facilitate filling and release, the cavity may have side walls that incline inward as the depth increases, and / or it may be desirable to have a vacuum opening at the bottom of the cavity. Leads to a vacuum source. Triangular polishing plates should be transferred onto the make-up layer precursor coating backing so that they are added upright or upright. Therefore, the shape of the cavity is designed to hold the triangular polished strip in an upright position.

In various embodiments, at least 60, 70, 80, 90 or 95 percent of the distribution surface cavities include a triangular polished plate. In some embodiments, gravity can be used to fill the cavity. In another embodiment, the means of production can be turned upside down and a vacuum can be applied to hold the triangular polishing plate in the cavity. Triangular polishing strips can be added, for example, by spraying, fluidized bed (air or vibration) or electrostatic coating. Excess triangular polishing strips will be removed by gravity because all unretained abrasive particles will fall. The vacuum can then be removed to transfer the triangular polished strips to make layer precursor coated disc backing.

As mentioned above, after the desired number of cavities have been filled, more triangular-polished plates can be added than the number of cavities so that some of the triangular-polished plates remain on the distribution surface. These excess triangular-polished plates can often be blown off, wiped off, or otherwise removed from the distribution surface. For example, a vacuum or other force can be applied to hold the triangular-polished plate in the cavity and upside down the distribution surface to remove excess portion of the triangular-polished plate from the distribution surface.

In a preferred embodiment, the production tool is formed from a thermoplastic polymer such as polyethylene, polypropylene, polyester or polycarbonate from, for example, a metal master tool. The means of production of the means of production and the master touring used in their manufacture are, for example, US Pat. Nos. 5,152,917 (Pieper et al.), 5,435,816 (Spurgeon et al.), 5, 672,097 (Hoopman et al.), 5,946,991 (Hoopman et al.), 5,975,987 (Hoopman et al.) And 6,129,540 (Hoopman et al.), And the United States. It can be found in Patent Application Publication Nos. 2013/03444786 (A1) (Keipert) and 2016/0311084 (A1) (Culler et al.).

In a preferred embodiment, the production tool is manufactured by additive manufacturing or "3D printing" of a suitable thermoplastic, thermosetting or radiation curable resin.

When the triangular-polished plate is embedded in the make-up layer precursor, the make-up layer precursor is at least partially cured to maintain the orientation of the minerals while adding the size layer precursor. Typically, this involves B-stepping the make-up layer precursor, but it is also possible to use a higher degree of curing if desired. B-stepping can be achieved using heat and / or light, and / or using a curing agent, for example, depending on the nature of the selected make-up layer precursor.

The size layer precursor is then added onto the make-up layer precursor and the triangular-polished plate, which are at least partially cured. The sizing layer can be formed by coating the main surface of the backing with a curable sizing layer precursor. Size layer precursors include, for example, adhesives, phenolic resins, aminoplast resins, urea-formaldehyde resins, melamine-formaldehyde resins, urethane resins, free group polymerizable polyfunctional (meth) acrylates (eg pendants α, β-unsaturated). It can contain groups, acrylated urethanes, acrylated epoxies, aminoplast resins with acrylated isocyanurates), epoxy resins (including bis-maleimide and fluorene modified epoxy resins), isocyanurate resins and mixtures thereof. When the make-up layer is formed by using the phenol resin, it is preferable that the size layer is formed by using the phenol resin as well. The size layer precursor is any known coating method for adding a size layer to the backing, including roll coating, extrusion die coating, curtain coating, knife coating, gravure coating, spray coating, etc. Can be added by. If desired, the presized layer precursor or make layer precursor according to the present disclosure can also be used as the size layer precursor.

Also, depending on the intended use, the type of abrasive particles, and the nature of the coated abrasive disc being prepared, the weight of the size layer will necessarily vary, but is usually 1 or 5 gsm to 300, 400, and more. Is in the range of 500 gsm or more. The size layer precursor is any known coating method for applying the size layer precursor (eg size coat) to the backing, including, for example, roll coating, extrusion die coating, curtain coating and spray coating. Can be added by.

In addition, the size layer precursor, and typically the partially cured make-up layer precursor, is sufficiently cured to provide a usable coated abrasive disc. Normally, this curing step requires thermal energy, but other forms of energy, such as radiation curing, can also be used. Useful forms of thermal energy include, for example, heat and infrared radiation. Illustrative sources of thermal energy include ovens (eg, festoon ovens), heating rolls, hot air blowers, infrared lamps and combinations thereof.

In addition to the other components, the binder precursors in the make-up and / or pre-size layer precursors of the coated polished discs according to the present disclosure, if present, are optionally catalysts (eg, thermal activation). It can contain a catalyst or photocatalyst), a free radical initiator (eg, a thermal initiator or photoinitiator), and a curing agent to facilitate curing. Such catalysts (eg, thermal activation catalysts or photocatalysts), free radical initiators (eg, thermal initiators or photoinitiators) and / or curing agents include, for example, those described herein. It may be of any type known for use in.

In addition to other components, make-up layer precursors and size layer precursors can further include, for example, optional additives to modify performance and / or appearance. Illustrative additives include grinded additives, fillers, plasticizers, wetting agents, surfactants, pigments, coupling agents, fibers, lubricants, thixotrope materials, antistatic agents, suspending agents and / or dyes. Can be mentioned.

Exemplary milling additives, which may be organic or inorganic, include halogenated organic compounds such as waxes, tetrachloronaphthalene, pentachloronaphthalene and chlorinated waxes such as polyvinyl chloride, sodium chloride, potassium glacial stones, etc. Halide salts such as sodium glacial stone, ammonia glacial stone, potassium tetrafluoroborate, sodium tetrafluoroborate, silicon fluoride, potassium chloride, magnesium chloride, as well as tin, lead, bismuth, cobalt, antimony, Examples include metals such as chloride, iron, and titanium and their alloys. Examples of other milling additives include sulfur, organic sulfur compounds, graphite and metal sulfides. A combination of different milling additives can be used.

Exemplary antistatic agents include conductive materials such as vanadium pentoxide (dispersed in sulfonated polyester, for example), wetting agents, carbon black and / or graphite in the binder.

Examples of useful fillers for the present disclosure include silica such as quartz, glass beads, glass bubbles and glass fibers, talc, clay, (montmorillonite) feldspar, mica, calcium silicate, calcium metasilicate, aluminokei. Silicates such as sodium silicate and sodium silicate, calcium sulfate, barium sulfate, sodium sulfate, aluminum / sodium sulfate, metal sulfates such as aluminum sulfate, gypsum, vermiculite, wood flour, aluminum trihydrate, carbon black , Aluminum oxide, titanium dioxide, feldspar, feldspar, and metal sulfates such as calcium sulfate.

Optionally, the supersize layer can be added to at least a portion of the size layer. If present, supersizes usually include milling additives and / or antiloading materials. The optional super-sized layer can serve to prevent or reduce the accumulation of chips (material polished from the workpiece) between the abrasive particles, and this accumulation of chips is the ability to cut the coated abrasive disc. Can be dramatically reduced. Useful supersize layers are typically ground additives (eg potassium tetrafluoroborate), metal salts of fatty acids (eg zinc stearate or calcium stearate), salts of phosphate esters (eg potassium behenyl phosphate). , Phosphates, urea-formaldehyde resins, mineral oils, crosslinked silanes, crosslinked silicones and / or fluorochemicals. Useful super-sized materials are further described, for example, in US Pat. No. 5,556,437 (Lee et al.). Generally, the amount of milling additive incorporated into the coated abrasive product is from about 50 to about 400 gsm, more typically from about 80 to about 300 gsm. The supersize can contain a binder, such as a binder used to prepare a size layer or make-up layer, but it is not necessary to have any binder.

Further details regarding a coated polishing disc comprising a polishing layer fixed to the backing, wherein the polishing layer comprises polishing particles and a make-up layer, a size layer and an optional super-sized layer, are well known. For example, U.S. Pat. Nos. 4,734,104 (Broverg), 4,737,163 (Larkey), 5,203,884 (Buchanan et al.), 5,152,917 (Pieper). Et al.), No. 5,378,251 (Culler et al.), No. 5,417,726 (Stout et al.), No. 5,436,063 (Follett et al.), No. 5,469,386. (Brover et al.), No. 5,609,706 (Bendict et al.), No. 5,520,711 (Helmin), No. 5,954,844 (Law et al.), No. 5,961,674 No. (Gagliardi et al.), No. 4,751,138 (Banger et al.), No. 5,766,277 (DeVoe et al.), No. 6,077,601 (DeVoe et al.), No. 6,228 , 133 (Turber et al.) And 5,975,988 (Christianson).

The coated polishing discs according to the present disclosure are useful for polishing workpieces, for example, by off-hand polishing using a handheld right angle grinding machine. Preferred workpieces include weld beads (eg, mild steel welds in particular), flushes, gates and riser-off castings.

In the first aspect of the selected embodiment of the present disclosure, the present disclosure
Disc backing with outer circumference and
A polishing layer placed on top of the disc backing, comprising a triangular polishing plate that is secured to the main surface of the disc backing by at least one binder material, with the triangular polishing plate extending outward toward the outer circumference. With a polishing layer, which is located at least 70 percent (preferably at least 80 percent, more preferably at least 90 percent) of regularly spaced locations along an arithmetic spiral pattern.
Each of the triangular polished plates has its own top and bottom surfaces connected to each other and separated by three side walls.
Each side wall of at least 90 percent of each of the triangular-polished plaques faces the disc backing and is located close to the disc backing, longitudinally within 10 degrees tangential to the arithmetic spiral pattern. Provided is a coated polishing disc to be aligned.

In a second embodiment, the present disclosure comprises a triangular-polished plate having an average thickness and an arithmetic spiral pattern having a pitch of 1.2 to 3 times the average thickness of the triangular-polished plate. A coated polishing disc according to the first embodiment is provided.

In a third embodiment, the present disclosure provides a coated polishing disc according to the first or second embodiment, wherein the polishing layer further comprises crushed polished particles or non-polished particles.

In a fourth embodiment, the present disclosure provides a coated polished disc according to any one of the first to third embodiments, wherein the disc backing comprises a vulcanized fiber.

In a fifth embodiment, the present disclosure comprises a first embodiment to a fourth embodiment in which the polishing layer comprises a make-up layer and a size layer arranged on the make-up layer and the triangular polishing strip. A coated polishing disc made of any one of the above is provided.

In a sixth embodiment, the present disclosure provides a coated polishing disc according to any one of the first to fifth embodiments, wherein the triangular polishing strip contains alpha alumina.

In a seventh embodiment, the present disclosure provides a method of polishing a workpiece, the method of which is a polishing layer of a coated polishing disc according to any one of the first to sixth embodiments. This includes frictionally contacting a portion with the workpiece and moving at least one of the workpiece and the coated polishing disc with respect to the other to polish the workpiece.

In an eighth embodiment, the present disclosure provides a method of polishing a workpiece according to a seventh embodiment, wherein the substrate comprises a mild steel weld and the polishing layer contacts the mild steel weld.

In a ninth embodiment, the present disclosure provides a method of manufacturing a coated abrasive disc.
Placing the curable make-up layer precursor on the main surface of the disc backing,
Adhesion of the triangular polishing strips into the curable make-up layer precursor, where the triangular polishing strips are regularly spaced along an arithmetically spiral pattern that extends outward toward the outer circumference. At least 70 percent (preferably at least 80 percent, more preferably at least 90 percent)
The triangular polishing plate comprises a triangular polishing plate, and each of the triangular polishing plates has a top surface and a bottom surface, which are connected to each other and separated by three side walls.
At least 90 percent of each side wall of each of the triangular polished strips facing the disc backing and placed in close proximity to the disc backing is longitudinally within 10 degrees of the tangential to the arithmetic helix pattern. Aligned, glued and
To provide a make-up layer by at least partially curing the curable make-up layer precursor.
Placing the curable size layer precursor on the make-up layer and the triangular polishing plate,
Curable Size Layer The precursor is at least partially cured to provide a size layer.

In a tenth embodiment, the present disclosure comprises a triangular-polished plate having an average thickness and an arithmetic spiral pattern having a pitch of 1.2 to 3 times the average thickness of the triangular-polished plate. The method according to the embodiment of 9 is provided.

In the eleventh embodiment, the present disclosure provides a method according to a ninth embodiment or a tenth embodiment, wherein the polishing layer further comprises crushed polished particles or non-polished particles.

In a twelfth embodiment, the present disclosure provides a method according to any one of the ninth to eleventh embodiments, wherein the disc backing comprises a vulcanized fiber.

In a thirteenth embodiment, the present disclosure provides a method according to any one of the ninth to twelfth embodiments, wherein the triangular polishing strip comprises alpha alumina.

The purposes and advantages of this disclosure are further illustrated by the following non-limiting examples, but the specific materials and amounts thereof, as well as other conditions and details described in these examples, are described in this disclosure. It should not be construed as an unreasonable restriction.

Unless otherwise stated, all parts, percentages, ratios, etc. in the Examples and the rest of this specification are by weight. Unless otherwise stated, all reagents are described, for example, in St. Missouri. It can be obtained, available, or synthesized by a known method from a chemical vendor such as Sigma-Aldrich Company at Louis. The abrasive particles used in the examples are reported in Table 1 below.

Example 1
A 7-inch (178 mm) circular plastic transfer tool consisting of an array of triangular cavities with a geometric structure as shown in PCT Patent Publication International Publication No. 2015/100018 (A1) (Adefris et al.) Was prepared by 3D printing. .. In the transfer tool pattern, as shown in FIGS. 4 and 4A-4D, all cavity openings were arranged substantially towards the edge with respect to the grinding direction of the rotating coated abrasive disc. It was a continuous spiral from the center to the edge. The spacing of the cavities along the length of the spiral is about 9 per inch (3.5 per centimeter), and the spiral pitch is about 30 rows per inch (11.8 rows per centimeter). )Met. The total number of cavities on the disc was about 10,000. The transfer tool was treated with a molybdenum sulfide spray lubricant (obtained under the trade name MOLYCOAT from the Dow Corning Corporation in Midland, Michigan) to facilitate the release of abrasive particles.

Excess abrasive particles AP1 were added to the surface of the transfer tool with the cavity opening and the tooling was shaken from side to side by hand. The transfer tooling cavity was immediately held upside down and filled with AP1 particles aligned along the long axis of the cavity. The process was repeated until additional AP1 was added and more than 95 percent of the transfer tooling cavities were filled with AP1 particles. Excess particles were removed from the surface of the transfer tool, leaving only the particles contained within the cavity.

The make-up resin is 49-part resol-phenolic resin (formaldehyde: phenol, a base-catalyzed condensate with a molar ratio of 1.5: 1 to 2.1: 1) and 41-part calcium carbonate (HUBERCARB, Quincy, Illinois). Huber Engineered Materials) and 10 parts of water were prepared by mixing. 2.8 grams of make-up resin brushed with a vulcanized fiber web (DYNOS VULCANIZED FIBER, 7 inches (17.8 cm) x 0.83 mm thick" with a central hole of 0.875 inches (2.22 cm). It was added to DYNOS GmbH) located in Troisdorf, Germany.

The transfer tool filled with AP1 was placed on a 7 inch x 7 inch (18 cm x 18 cm) square wooden plate with the cavity side up. The make-resin-coated surface of the vulcanized fiber disc was brought into contact with the filled transfer tool and another 7 "x 7" (18 cm x 18 cm) square wooden board was placed on it. The resulting assembly was inverted while maintaining rigid contact so that it fell from the bottom to the surface of the make-up resin first, and then tapped gently to transfer AP1 particles from the transfer tool. The vulcanized fiber disc backing was then dropped from a transfer tool that was no longer substantially particle-free, resulting in an AP1-coated vulcanized fiber disc that replicated the transfer tooling pattern.

Drop coat filler particles consisting of AP2 were added in excess to the wet make-up resin and stirred until the entire exposed make-up resin surface was filled with AP2 to volume. The disc was flipped to remove excess AP2. The amount of AP2 added was 16.0 +/- 0.5 g.

The make-up resin was partially cured in the oven by heating at 70 ° C. for 45 minutes, then at 90 ° C. for 45 minutes, and then at 105 ° C. for 3 hours. The disc was then coated with 14.5 +/- 0.2 grams of conventional cryolite-containing phenol-sized resin and cured at 70 ° C. for 45 minutes, followed by curing at 90 ° C. for 45 minutes, followed by It was cured at 105 ° C. for 16 hours. Using Example 1, the AISI 1020 steel pipe was ground using the Grinding Test Method A. Grinding performance results are reported in Table 2.

Example 2
Example 2 was prepared as described in Example 1. The amount of AP2 drop-coated secondary particles was 11 +/- 0.1 grams and the amount of cryolite-sized resin was 13.7 +/- 0.1 grams. Using Example 2, AISI 1018 mild steel was searched using Grinding Test Method B. AISI 1018 mild steel is 0.18 percent carbon, 0.6-0.9 percent manganese, 0.04 percent (maximum) phosphorus, 0.05 percent (maximum) sulfur, and 98.81 by weight. It has a composition of ~ 99.26% iron. Grinding performance results are reported in Table 2.

Comparative Example A
Comparative Example A was a commercially available, electrically coated vulcanized fiber disk (obtained under the trade name 982C Grade 36+ from 3M Company, located in Saint Paul, Minnesota). Using Comparative Example A, AISI 1018 mild steel was ground using Grinding Test Method B. Grinding performance results are reported in Table 2.

Comparative Example B
Comparative Example B was prepared as described in Example 1, except for the following. The transfer tool cavities were arranged in a rectangular array pattern as described in Example 4 of US Pat. No. 9,776,302 (Keipert). The cavity array is 17 per inch (6.7 per cm) in both horizontal and vertical directions, with a total of 289 per square inch (44.8 per square cm). It was density, i.e. about 10950 cavities throughout the tool. The transfer tool was filled with AP1 particles. The amount of make resin was 3.0 +/- 0.1 g. The drop-coated secondary particles were 15.3 +/- 0.2 grams of AP2. Cryolite size resin levels were 14.6 +/- 0.1 grams. Using Comparative Example B, the AISI 1020 steel pipe was ground using Grinding Test Method A. Grinding performance results are reported in Table 2.

Comparative Example C
Comparative Example C was prepared as described in Comparative Example B. The transfer tool was filled with AP1 particles. The amount of make resin was 3.5 grams. The drop-coated secondary particles were 9.4 grams of AP2. Cryolite-sized resin levels were 12.1 grams. Using Comparative Example C, 1018 mild steel was ground using Grinding Test Method B. Grinding performance results are reported in Table 2.

Grinding test method A
Grinding performance of various discs was evaluated by grinding 1020 mild carbon steel pipes using the following procedure. A 7-inch (17.8 cm) diameter coated polishing disc for evaluation is attached to a drive motor that operates at a constant rotational speed of 6000 rpm, and a 7-inch (17.8 cm) ribbed disc pad surface plate (17.8 cm). It was fixed using (obtained as 051144 EXTRA HARD RED RIBBED) from 3M Company in St. Paul, Minnesota. The grinding machine is activated and under a controlled force of 20 lbs on the end face of a pre-weighed 1020 steel pipe 1 inch (2.54 cm) in diameter and 0.125 inch (3.175 mm) in wall thickness. I was pressed. Under these conditions, the workpiece was ground with a grinding interval of 3.2 seconds. Following each 3.2 second interval, the workpiece was cooled to room temperature and weighed to determine the amount of grinding for the polishing operation. The end point of the test was determined when the amount of grinding was less than 12 grams per cycle. Test results were reported as incremental grinding amount (g / cycle) per interval and total stock removed (g).

Method B
Grinding performance of various discs was evaluated by grinding 1018 mild carbon steel bars using the following procedure. A 7-inch (17.8 cm) diameter coated polishing disc for evaluation is attached to a drive motor that operates at a constant rotational speed of 5000 rpm, and a 7-inch (17.8 cm) ribbed disc pad surface plate (17.8 cm). It was fixed using (obtained as 051144 EXTRA HARD RED RIBBED) from 3M Company in St. Paul, Minnesota. The grinding machine was activated and pressed against the end face of a 1 x 1 inch (2.54 x 2.54 cm) pre-weighed 1018 steel bar under controlled force. Under these conditions, the workpiece was ground with a grinding interval of 13 seconds. Following each 13 second interval, the workpiece was cooled to room temperature and weighed to determine the amount of grinding for the polishing operation. The end point of the test was determined when the amount of grinding was less than 15 grams per cycle. Test results were reported as incremental grinding amount (g / cycle) per interval and total stock removed (g).

The results reported in Table 2 (below) were obtained according to Grinding Tests.

All references, patent documents or patent applications cited in the above patent applications are incorporated herein by reference in their entirety in a consistent manner. In the event of any inconsistency or denial between a portion of the incorporated references and a portion of the present application, the information in the above description shall prevail. The above description given to enable the practice of a patented disclosure by a person skilled in the art should not be construed as limiting the scope of the present disclosure, and the scope of the present disclosure is the scope of the claims. And all its equivalents.

Claims (13)

It is a coated polishing disc,
Disc backing with outer circumference and
A polishing layer disposed on the disc backing, comprising a triangular polishing strip secured to the main surface of the disc backing by at least one binder material, with the triangular polishing strip facing the outer periphery. With a polishing layer, which is placed at least 70 percent of the regularly spaced locations along the outwardly extending arithmetic spiral pattern.
With
Each of the triangular polished plates has its own top and bottom surfaces connected to each other and separated by three side walls.
Each side wall of at least 90 percent of each of the triangular polished plates faces the disc backing and is located close to the disc backing, within 10 degrees tangential to the arithmetic spiral pattern. Aligned vertically,
Coated polishing disc. The coating polishing according to claim 1, wherein the triangular polishing plate has an average thickness, and the arithmetic spiral pattern has a pitch of 1.2 to 3 times the average thickness of the triangular polishing plate. disk. The coated polishing disc according to claim 1, wherein the polishing layer further contains crushed polishing particles or non-polishing particles. The coated polishing disc according to claim 1, wherein the disc backing includes a vulcanized fiber. The coated polishing disk according to claim 1, wherein the polishing layer includes a make layer, a size layer arranged on the make layer and the triangular polishing plate. The coated polishing disc according to claim 1, wherein the triangular polishing small plate contains alpha alumina. Of the substrate and the coated polishing disc, in order to bring a part of the polishing layer of the coated polishing disc according to any one of claims 1 to 8 into frictional contact with the substrate and to polish the substrate. A polishing method that includes moving at least one to the other. The method of claim 7, wherein the substrate comprises a mild steel weld and the polishing layer contacts the mild steel weld. It is a method of manufacturing a coated polishing disc.
Placing the curable make-up layer precursor on the main surface of the disc backing,
By adhering the triangular polishing plates into the curable make-up layer precursor, the triangular polishing plates are arranged at regular intervals along an arithmetic spiral pattern extending outward toward the outer circumference. Located in at least 70% of the locations,
The triangular-polished plate comprises a triangular-polished plate, and each of the triangular-polished plates has a top surface and a bottom surface that are connected to each other and separated by three side walls.
Each one side wall of at least 90 percent of each of the triangular polished plates is placed in close proximity to the disc backing in its entirety and longitudinally within 10 degrees of the tangential direction to the arithmetic spiral pattern. Aligned, glued and
To provide a make-up layer by at least partially curing the curable make-up layer precursor.
Placing the curable size layer precursor on the make-up layer and the triangular-polished plate.
To provide a size layer by at least partially curing the curable size layer precursor.
Including methods. The method of claim 9, wherein the triangular-polished plate has an average thickness and the arithmetic spiral pattern has a pitch of 1.2 to 3 times the average thickness of the triangular-polished plate. The method of claim 9, wherein the abrasive layer further comprises crushed abrasive particles or non-abrasive particles. The method of claim 9, wherein the disc backing comprises a vulcanized fiber. 9. The method of claim 9, wherein the triangular polishing strip comprises alpha alumina.

Images